The building evacuation problem with shared information

In this article, the Building Evacuation Problem with Shared Information (BEPSI) is formulated as a mixed integer linear program, where the objective is to determine the set of routes along which to send evacuees (supply) from multiple locations throughout a building (sources) to the exits (sinks) such that the total time until all evacuees reach the exits is minimized. The formulation explicitly incorporates the constraints of shared information in providing online instructions to evacuees, ensuring that evacuees departing from an intermediate or source location at a mutual point in time receive common instructions. Arc travel time and capacity, as well as supply at the nodes, are permitted to vary with time and capacity is assumed to be recaptured over time. The BEPSI is shown to be NP‐hard. An exact technique based on Benders decomposition is proposed for its solution. Computational results from numerical experiments on a real‐world network representing a four‐story building are given. Results of experiments employing Benders cuts generated in solving a given problem instance as initial cuts in addressing an updated problem instance are also provided. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008     

Understanding women at war: a mixed-methods exploration of leadership in non-state armed groups

ABSTRACT

Recent efforts aimed at understanding women’s contributions to nonstate armed groups have produced large-scale data sets on female combatants (Wood and Thomas 2017) and more limited data on women’s roles as supporters and leaders in armed groups (Henshaw 2016; 2017, Loken 2018). The present study aims to build on this literature by providing new data on the scope of women’s leadership in insurgent groups. While existing quantitative literature has focused mostly on the experience of female combatants, we argue that the presence of women in leadership roles is crucial to understanding how gender might influence the outcomes of insurgency. We introduce new data on over 200 insurgent groups active since World War II. While our analysis confirms earlier small-sample work demonstrating women’s presence in leadership roles, a qualitative analysis reveals that leadership is often gendered–revealing patterns of tokenization and tracking women to low-prestige leadership roles. At the same time, our findings challenge past research on jihadist organizations, showing limited expansion in the authority of women.